<template>
   <div>这是子组件{{cat}} <button @click="changeSgm">改变msg</button></div>
    
</template>

<script>
export default {
    name: 'Son',
    props:['cat'],
    methods:{
        changeSgm() {
            this.$emit('changeMsg','王婷婷')
        }
    }

}
</script>

<style>

</style>